Project - Low Pressure
I have done low-pressure conversions to my two older Spyders about 1 1/2 years ago and am very happy with the performance that it has provided me. I have also done several conversions to Spyders that have entered my shop with good results. However, I had not documented the conversion from start to finish. Then again, I had not envisioned myself having my own web site.

In this article, I will describe a transformation of a Kingman Spyder 2-in-1 Java Edition from a stock marker right out of the box to an efficient low-pressure marker. I will try and provide pictures as I go. Details such as comparison of different items that are installed into the marker and a performance comparison. You could say that this an attempt to confirm that converting to low pressure (or LP as it will be referred to) is something to look at as an upgrade. For more information on LP, read my article about low pressure. For those wondering if they can do a low pressure conversion to their Spyder or Spyder clone, the answer is YES!!! Even the electronic ones like the E-99. The only exception is the Kingman EM1 and the AMG. The AMG is already LP out of the box. However, some of the items that I list here will help to improve the AMG for lower operating pressure.

Be patient with this article as it will take some time to find time to get parts needed, adding the parts and comparing them with each other, and finding the time to add the information to this page. Not only that, but it will be an expense to test out all the items that I wish to have. I already have these parts in house. There is also the "consumables" like air and paint.
Without any further delay, let's get started.

Java Spyder 2-in-1
I started off with a Java 2-in-1 Spyder by Kingman International. All stock, the MSRP is about $140.00. Though, I have seen them for $100.00. This maker is a step up from a Spyder Compact 2000. What makes this particular Spyder appealing is that you can use a tank screwed onto the bottom of the grip. Or, unscrew the bottomline and air line from the vertical adapter and run the tank vertically from the ASA.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

The Bob Long is identical to the Kingman stock bolt in many ways. The only reason that I am using this is because it still has the venturi. All of my other bolts have there Venturi removed. I have one other bolt that I have in my toolbox that is not shown and will not be used in this project. It is the 32degree Titanium bolt. This has a 7-hole venturi that is drilled in and not removable. I had recently acquired for testing purposes the Spudenuk'l bolt.

These will be the regulators that I have chosen to use in this project.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

A non-purchased item is polishing the internals. The two pictures above shows 3 different strikers. The top picture showing 2 strikers are that of the slim striker that the 2-in-1 uses. The striker (top) is polished. Another striker that I had tested is a Titanium Striker offered by Dark Horizon. I had met with them personally and had them make a striker according to my specs. What they turned out is the above picture. It is lighter than the standard striker (more than 50% less) than the weight of a standard striker.

Other items that are not pictured that I will be utilizing is a 32degree spring kit. I prefer this over the Maddman spring kit because of the number of valve springs included. The Maddman comes with one valve spring. The 32degrees comes with three. But don't consider the Maddman inferior. They do have a nice trigger spring to smooth out that rough stock trigger spring.

To make sure that the velocity is the same all around when comparing the different pieces is a lockable velocity adjuster. This way I can lock the knob in place while I switch out the different items. The original could unscrew itself either during firing or taking apart the marker.
An air line that I will be using is the stainless steel braided air line. You can use macroline if you wanted to. But I just do not like them because they are breakable.

The Tests
Since I had gotten all the parts and was ready to go, I had a difficult time in deciding which direction to go. I knew what I had to work with and what my goal was for this article. Documenting was the tough part of this article.

I must add too that not all Spyders will act in the same way due to the inconsistancies that Kingman production line puts out. So, you may get slightly different results from your Spyder 2-in-1 than what I will show in this article. But I would not be too concerned. Whatever you do, I am sure you will have a Spyder shooting below 400psi.

Barrel to be used in testing is the the stock barrel. Not concerned with length or porting yet. Just wanted to get some stats posted. This is considered a medium bore barrel. So I shall be using medium bore paint. Java Classic by Kingman fits very well.

I will also set the marker up with the stock parts so that the added item that I am testing will go up or down. I decided to use a Bob Long regulator set at 750psi to ensure accurate air. The velocity to start out was set at 275fps. The type of air source that I will be using is a Pure Energy 68cu 3,000psi tank. The reason I am using compressed air is because it is very stabile.

The Bolts
Well, the bolt is typically the first thing to add/change to for LP. Many will think that the bolt will magically add range, accuracy, and less ball breaks to LP and non-LP setups. I do not believe this. First of all, I like to think as the entire marker as a valve which can be broken down to its individual components. The bolt is just one component that when air is rushing into it, the air is directed to the back of the ball. There is nothing inside the bolt that will really increase it's performance.

Seeing that we are wanting an LP setup, high flowing components is a must. We are trading the literal brute force of 850psi for area and lower operating pressure. And the bolt, even though nothing is special about them, can and will vary in how high flowing it is. The chart below shows the averages of ten shots.

* It was brought to my attention that Spudnuk'l may not be in business. To date, I have yet to verify this. I can suggest one other bolt that has past through my shop that I was able to try out. But not officially. It is just as good as the Spudnuk'l bolt. It is the Tigershark bolt. Do check them out. I do hope that I can make an official recommendation to this bolt after some testing.

So, as you can see, the AKA bolt seems to be the most high flowing of all bolts tested by about 30fps. That translates in a reduction of time the valve has to be open. The S-74 is a close second with a modified stock bolt being third. The most unlikely bolt is the Bob Long (same as a unmodified stock bolt) with the venturi still in.

Many of you may know that I am not a big fan of these Nylon/Delrin bolts. Mainly because they tend to soak in high humidity, broken paintball goo, or oil. When this happens, these types of bolts seems to swell and get stuck in the receiver. If not that, then they will cause some excess friction. Another reason is the lack of o-rings. Since Kingman doesn't hold much tolerances in the reciever, these o-rings-less bolts tend to let air travel all around the bolt as well as through it. This translates into excess air used to fire the paintball and/or blowback. I found that the Spudnuk'l bolt to have the nylon construction and have groves for o-rings all in one. And, they are at a reasonable price. Though the AKA is best for LP, the Spudnuk'l bolt is a close 2nd and should be considered.

The Regulator
A regulator is a great all around upgrade and should be one of the top three along with an agitating hopper and a new barrel. A regulator will take the inconsistant pressures that a tank (CO2 or Nitro) and feed the marker a tighter range of psi to stabilize the shot to shot velocity. In these series of tests, I will be using nitro because of the Air America Vigilante. The Vigilante is a nitro/compressed air only regulator. Using CO2 with this regulator can cause internal damage.

The Palmer came out ahead of the rest as being the best flowing regulator. Recharge was not bad. The vigilante is better in recharge. But, for those that are using CO2, the Palmer is the way to go. The Bob Long is good for LP with CO2 use. Was able to get my hands on a WGP regulator for this testing. That turned out to be the worst.

The LPC
Whether you call it a low pressure cell, low pressure chamber, or just LPC, there is not much to the overal construction. All it is for is to hold extra gas that has been measured out to a certain psi. It is simply a tube with an open end. There may be differences in how deep the holes are. Just recently, it was brought to my attention that ShockTech offers a 5" LPC, but the hole is no deeper than the stock LPC.

Even though the there is a difference in the internal area of the LPC, they both yielded the same velocity. So, I would not worry about changing the stock LPC.

Vertical Adaptor
For some, this can be the main culprit of re-cocking issues of an LP setup besides spring tension. If you decide to modify the vertical adaptor, you must be careful not to reem the hole too much. You could render the VA useless because you breeched the screw hole.

As you can see, both the Bob Long and 32degree VA are about identical in providing the same velocity. The ironic thing between them is that dimensionally, they are the same. Since this is the best in air flow, look for either that is least expensive.

Valve
Here is an important item for LP. The valve. There are other issues to a non-working LP setup that could stem from this.

The AKA and Rocket seems to be the best in air flow. I did experience some re-cocking issues. I am not concerned with it since there are mostly not so high flowing parts used. Playing with the springs and installing higher flowing parts should help. The Diamond Labs equaled the AKA. However, the DL is no longer around. Shame, made an excellent product at half the cost of the AKA and about $10 less than the Rocket. The next best was the 32degrees valve and Omega valve. Both are the same basic design just like the Taso valve. They are high flowing. But for LP, there are better ones. The Omega is nice since they are made of Titanium and has an adjustable air chamber. Sounds nice. Just not the best. No recocking issues here. The quick, spur of the moment, modification to the stock valve panned out rather well. Many have copied the 32degrees valve by "milling" out the top portion. All that needs to be done to a stock valve body is to drill the existing top hole bigger and a few other minor reaming of the inside. I should be able to make an article on this soon.

Valve Pin
I was debating if I should add this or not since it is hard to get valve pins individually. Not only that, but the valve pins are made specifically for a valve (ie. AKA, Diamond Labs). I could show the difference between the stock, modified stock, and 32degrees pin. Could be information useful to those with air flow problems even if you are not going LP.

The 32degrees valve pin is the best of the bunch that will not only fit in the Magnaport Valve, but also the stock valve body. Unfortunately, you cannot get the pin seperately. The modified stock pin did well. But i will say that filing it down is more work. I suggest getting the 32degrees valve and be done with it.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

There is the difference between polished and not polished. May not look like a big difference. But it may lead to an AKA valve to recock or not. Plus, helps to get a few extra ounces of performance out of the marker. As for the modified Titanium striker, excellent results. This is not the typical titanium striker off of Dark Horizon shelf. This has been modified to my standards. If you want a similar striker like mine, contact them and tell them that OtterSC Customs sent you. Tell them that you want the design that Otter had made. They have them in Slim and Fatty striker style. And no, I am not associated with Dark Horizon or get any kick back from them for advertising them. Just want to make known somebody that has a good product. The no name titanium striker was originally thought as being that of Dark Horizon. I appreciate Dark Horizon taking time out of there busy schedule to meet with me. The products that they have were slightly different from the no-name one. It was just a light. However, the finish was not the same.

You may wonder how a striker will affect the velocity of a paintball when all it is doing is hitting the valve open. Well, good question. Because of the striker is either polished or lighter with a smoother finish, there is less resistance. Less resistance equals higher reaction speeds of the striker (and bolt, since they are attached).

What Parts will I use
That is the information that I have found. Now you can see the difference in performance in the different parts. It all could be used for the non-LPer to upgrade that is needing more velocity.

Now, to setup the marker. What components I will use in the 2-in-1 is the following.

This is probably the best, yet most expensive setup. Approximate price range is $200 to $350 depending on what prices are charged by your supplier.
Another interesting note is the use of the modified titanium striker. Between the two titanium strikers tested, the weights were very close. However, with the modified titanium striker, i was able to reduce my operating pressure significantly, as i will explain later.

If I was on a tight budget, my component list would look something like the following...

As you can see and compare the two component lists, the second one is consisting of modified stock parts. Severly low cost. Possibly a difference of $125. The components in the second list doesn't garentee that the setup will work at peak efficiently. It is possible for it to work at around 350-400psi. But most likely not depending how well the parts match with Kingmans tolerancing.

Do notice the two constants between the two lists. The regulator and spring kit. A spring kit is important to change the tension of springs that will enable the valve to be open for a longer time or not. Possibly too, the recocking issue. But a specific name spring kit is not needed. You could get away with a Chameleon Kit rather than a 32degree kit.

The second constant is a Palmer Stabilizer listed in both lists. Any regulator will do, so long it is high flowing. One regulator that I did not test, but know it is the best, is the Smart Parts MaxFlo. These are expensive. But from past experience, this regulator can operate three or more markers at the same time. The thing to keep in mind is that your LP setup is as good as the components. There are shortcuts that can be taken. But the quality of a regulator is very important. You get what you pay for. All of the ones I tested for this article are high quality and high flowing. High flowing is the operative word. There are others that are good for LP that I did not test. Like the MacDev Gladiator and AKA Sidewinder. Regualtors like the WGP and PMI, as well as Kingman, are air restrictive and not suitable for low pressure applications.

If you do the cheaper setup above, and it doesn't work, consider adding the following parts in order until it does work. Add them one at a time.

Polish Internals
Valve
32degrees Vertical Adapter

A side not for the AKA Valve. Many will say that it will not fit or work in thin striker Spyders like the Shutter. On the contrary, it will fit. Working right off the bat is what should be the question. You may have trouble getting the marker to recock. Not only that, but this valve should be run at 400psi or lower. Higher pressure may cause damage. But I can garentee you that it will work in thin striker Spyders. I have yet to work on one that has come through my shop and not work.

Another good thing to do for LP (or not), is polishing the internals. This will help things move smoother internally. The best thing for LP is less resistance. That is not limited to air flow. There is some restriction to the parts rubbing against eachother that can hinder the overall operation. Not all parts need polishing. Like the AKA bolt. The AKA bolt has a nice smooth finish as compared to the stock bolt.

I hope that you will use this information in the charts above to help you in deciding what you want to use and what changes to expect upon switching parts out. There are plenty of choices with the many aftermarket parts out there. I will say that if you want a setup that will work, then do consider spending the extra money and getting quality parts.

Putting it all together
Well, now that I have picked out all of the components, I can now put everything in. This is pretty easy task. It is much like totally disassmbling the entire marker. But in the process of reassembly, you put in the new components instead of the old.

Since I have taken everything apart, I will give it a thorough cleaning. All the dirt and grimmy oil is cleaned out. Soap and water does the trick for the body.

I will also do a trigger modification to the marker. Since I am putting in all this lovingness into the marker, why not. Lightening the sear also helps with some potential recocking issues.

Another consideration that I needed to address is a barrel for an LP setup. The stock is good enough. But i like something that is made just a little better. For LP, you want to keep as much air behind the ball as long as possible. So the least amount of porting is required. Barrels from Smart Parts has too much porting for LP. The LP setup will work, but not to it's fullest effiecncy. Barrels that are good quality are CP, DYE, J&J, and Lapco. Since I have done LP conversions before, I will go with a J&J since I like them and works well for LP.

One last detail. I had gotten a velocity adjustor with a locking wheel. As it is, the quick strip pin will not work due to lack of a slot. So, I did a quick strip pin modification to the velocity adjustor. All it needed was a good filing.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

Field Testing
After installing everything and testing for leaks, time to test out things and fine tune all the parts to work together. This step requires air, paint, and a chronograph as well as your basic field stripping tools. But the most important item that you will need is patience.

I need to find out the lowest pressure that the current spring configuartion will operate with. The stock springs is what is inserted. Basically what I do is set the velocity to 2/3 in and lock it in place. This is where it will remain. Practically a permanant setting. I will discuss later when this can be adjusted.

I start the regulator at 450psi. I start dry firing the marker. Every fifth shot, I will decrease the psi by 5-10units. The 1st and 2nd shot will not reflect the adjusted regulator. I keep doing this until the marker fails to recock. Once it fails to properly recock, make a note of the psi and spring combo. Add about 10 to 15psi. This is essentially the lowest psi that the marker will shoot at. This spring combo yielded a low psi of 375psi. Not bad. I am within LP country. But I like to see if I cannot bring that down more.

I turn off the air source and change springs. Generally, since we are trading the brute force of 850psi for a lower psi, the valve needs to be open longer. Typically, you will need to add a stronger main spring and/or add a weaker valve spring. I will only change the main spring for now to a stronger one. I will increase the regulators psi to 50 and dry fire the marker. I will reduce the psi until a failure to recock properly occurs. This should be lower than the previous springs.

Sure enough, it is lower. It reached 275psi. Now I want to see what PSI a different valve spring will be with a stock main spring. I insert a weak valve since I want the valve to be open longer. Repeat above. Turns out to be lower than the last spring combination of stock valve and strong main. Just a 70psi difference between the two in favor of the new valve spring/stock main combination. My last spring combo that I want to try is a strong main and a weak valve. I then test.

Well, the results were interesting. Because of the greater increase of the valve being open with the weakest valve and strong main, one would think that you will get a lower operating psi. However, since Kingman doesn't keep tolerances strict, this combination is not the lowest. The lowest pressure I was able to get was 320psi. So I guess I will use the weak valve/stock main spring combination since that yeilded the lowest pressure for me at 275psi.

Now that I have everything installed, tested for leaks, and now found the right spring combination for this marker, it is now time to chrono in a velocity. A good velocity for LP is between 280 and 285fps. You may not go as far as a marker shooting at 295fps. But that is only a 10 to 15 foot difference at the most. Well, I gassed up my marker and loaded a paintball. I did not add a full hopper as I will most likely be shooting a few paintballs just to get the velocity. Besides, if the marker starts burping, it would be a paint blender until I am able to cut off the air source.

Remember that we had the velocity adjustor locked in 2/3rds in. We are still not going to adjust it. A velocity adjustor will span 30-50fps in adjustment. What we want to do is have the regulator do all the work in getting and stabilizing the velocity. So I set the regulator for this spring combination.
I shot a ball over the chronograph. That came up short for a velocity. About 245fps. It doesn't take much to increase the velocity when you adjust the regulator. I increased the regulator to 280psi. Shot several shots to get the right adjustment. Closer. The velocity was 250fps.

More adjustment is needed. I could adjust the velocity adjustor and keep the regulator set at 280psi. But I will not. I will increase the regulator to 290psi and retest. I want to use the velocity adjustor for fine tuning during games and tournaments. Regulators will where into place and provide consistant pressure. I want to find that spot.

With the regulator set at 290psi, I shoot over the chronograph. Got it! 283fps with a deviation of plus or minus of 3 units either way. Just what I was looking for.

For those wondering about the cheaper way of doing an low pressure conversion, I installed the parts listed in my second list. There results were close to equal. The spring combination that was best for these parts were different. Could be how the parts work together. In this set up, it is a stock valve spring and a strong main spring.

I was also having trouble with recocking. Even after polishing the internals. So I added a 32degree vertical adaptor. My final operating pressure was 345psi and firing at an average velocity of 281fps. Not bad.

With both set ups, I have experienced a quieter Spyder, no ball breaks during two cases (4,000 paintballs) of paint each, doubled shots per fill, and accuracy that is very consistant.

Update - January '03: Since I first wrote this article, I had a good amount of tested items. Now, at the end of the year of 2002, two new products became available. The Maddman Rocket valve and the Dark Horizon Titanium Striker.

The Maddman Rocket gave equal (if not better) results of the AKA. It is a new look for a valve. What make it unique is that it doesn't require the need for a valve spring. It is built into the unit. Also, since it is equal in performance, there is one more plus. It is about half the price as an AKA valve, around $30-$35.00. It also suggests in the instructions that you plug the exhaust hole in the lower reciever. That is the hole that is located between the sear slot and the valve screw. I had threaded it and secured a set screw to plug it. The reason i did that is so that I could remove the set screw if needed. I will soon test to see the difference I get between the plugged and unplugged exhaust port.

The other item, the titanium striker, looks like a highly polished striker. Until you pick it up. The is the first thing that you will notice. I had met with Albert from Dark Horizon. Very nice gentleman. He caught wind that I had tested one of his strikers. He was suprised since it is a brand new product. I met with him and his team and I came to the conclusion that the one that I had tested were not from him. Rather from another similar custom shop. Further conversation, I had talked them into making me a striker with a small change. The results of this striker? Amazing!

My now current setup to this marker with the Rocket valve and new modified titanium striker, the operating pressure is at 230psi shooting at 280fps. i was able to have it recock down to 125psi. but the velocity was not useable. Efficiency has increased. Very close to doubling it. And I really have not sat down to really work out the kinks.

A final note on spring combinations. I get a lot of questions concerning what spring combo is best for an LP setup. The one that I mention above is one example. However, it is not the only combo to use. Finding the right spring combo for the best efficiency, one must use trial and error. I have 5 Spyders; all operating LP at 350 or lower. The marker for Project - LP has a weak valve/stock main spring combination. Another marker has a strong valve/stock main spring. Two other Spyders have a strong valve/weak main spring. The last one has a stock valve/strong main spring. All of these combos yielded well within the LP operating pressure and seems to be best efficiency.

Another question that I am asked is how do you know the marker is setup for best efficiency? Again, I will have to say trial and error. Having the lowest operating pressure will not yield the best efficiency. Ask any player that uses an AutoCocker setup for LP. Same goes with the Spyder. To know that the pressure is best for gas usage, make a note when you play. Estimating how full your tank is versus how much paint you use is good. Paint is usually purchased in cases of 2,000 and bagged individually in bags of 500. Simply measure every so often the velocity of your paint. If it seems to be slowing down, that means that your tank is getting low. Or, have your tank weighed after 500 shots. For those using HPA, you have a gauge that you can look at and measure. Remember, the right ball to barrel will help with efficiency. Not just for accuracy.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

Sometime in the near future, will be investing in a Check It 15* Assault block. They are just as high flowing as the 32degrees/Bob Long VA, with a different look.

Update - June '03: I had the opportunity to test out the Spudnuk'l Bolt and the Omega Valve. These items were borrowed from two players. I do thank them for allowing me to test these out and post the results for your LP project. See the above sections for the stats that I had gotten.

Update - March '04: I have gotten several questions about the type of gas used. Some have expressed that when they were using CO2, they got a very nice low pressure. However, when they changed to HPA (same day without changing any settings), the marker fails to recock.

Actually, they neede to increase the regulator for it to recock the marker. Some changes were significantly higher. I do not know for sure why. But, I do have a theory.

CO2 is a heavy gas. Probably why it is close to being a liquid. When you fire, the tank will cool and the gas will not evaporate from it's liquid state. HPA is air that we breathe. It takes a severe temperature change to cause it to be a different substance. In short, CO2 has a heavier mass than HPA. I do not know if this phenomina is true for N2.

Update - April '05: Not much was added. Just a new item to be added for consideration. The Insane Pain Nightstriker. Check out the results with the other strikers. Also added some more bolts, regulators, and valve.

Final Thoughts
In all, I am very happy with what I was able to accomplish and to be able to share with you. I will not be suprised by ones still not believing in what an LP can do dispite this article. The only real con, in my opinion, that they will be able to hold against low pressure is that it is expensive for a beginner marker like a Spyder. Why invest all that money into it when you can buy an AutoMag or AutoCocker? All I can say is that it is personal preference. I do hope that you find this article useful in helping you decide if converting to low pressure is worth while to you.

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes

(7:11:05 PM) Battlechaser: Did you just slaughter George Clooney and steal his mojo..?

"Death doesn't exist. It never did, it never will. But we've drawn so many pictures of it, so many years, trying to pin it down, comprehend it, we've got to think of it as an entity, strangely alive and greedy."
- from Ray Bradbury's Something Wicked this Way Comes